Device and method for tying a knot

ABSTRACT

An automatic machine that holds, inflates, then securely knots ordinary latex party balloons without using accessories includes a filling nozzle, surrounding clamps, and a balloon neck stretcher. Two closable jaws can be raised, lowered, advanced, retracted and twisted about the stretched neck so that a knot is formed in the stretched neck prior to release of the balloon. Mechatronics techniques make the required motions. An optional supply mechanism pre-mounts balloons on rows of nozzles on parallel sliding strips, so that a particular strip can be selected and moved to cause inflation and knotting.

FIELD

This invention relates to automated means for selecting, holding, inflating, securely knotting and then releasing latex party balloons or like objects.

BACKGROUND

The idea that a venue for a spectacular occasion, such as a party, a wedding, a ball, a civic reception, or a political meeting should be decorated with a profusion of latex balloons has been with us for many years. Actually blowing up and tying off the large number—perhaps in the hundreds or thousands—is notably time-consuming and is quite tough on the worker's hands. China intends to release 250,000 balloons at one event in the forthcoming Olympics. Furthermore, it is difficult to blow up each balloon to the same size and ensure that each one is equally slow to deflate so that the display remains visually acceptable for as long as possible. Previous attempts to solve the problem have often involved the use of either modified balloons or the provision of external sealing means such as clips, wire, or string. Commercially available machines intended to help a balloon artist supply a nozzle upon a surface with gas under pressure but no true knotting machines are known.

In addition to the need for balloons to be inflated and tied for large scale displays and occasions, there is also a need for apparatus allowing small numbers of balloons to be filled, tied and dispensed in a retail setting, with provision for a consumer to make choices of colour or type from a range. It will be appreciated that filling balloons with helium is difficult to arrange domestically or on a small scale, and that an automated means by which this could be achieved in a retail setting could be of advantage. Advances in mechatronics have provided basic apparatus with which a knotting machine could be made, but a functional procedure using particular components for the non-trivial task of forming a true knot remained to be developed.

PRIOR ART

The challenge of knotting distended party balloons has resulted in a number of prior patent publications. One group (including JP2005218795) provides a special kind of balloon. Another group relies on use of an accessory tie such as a piece of string or a clip; for example see WO2006/002686, US2004198146, US2002088894, U.S. Pat. No. 6,273,479, AT409341B, and U.S. Pat. No. 4,802,877. The third group provides balloon-holding devices for assisting in knotting a distended balloon by hand, using an overhand knot; such as U.S. Pat. No. 6,902,212, DE102004002803, US2003160453, U.S. Pat. No. 6,540,267, U.S. Pat. No. 6,325,426, U.S. Pat. No. 6,227,580, U.S. Pat. No. 6,082,785, U.S. Pat. No. 5,568,950, U.S. Pat. No. 5,611,578, and many others. In all viewed cases, motive power is provided by the human hand or hands. No known prior art describes a machine that takes an empty balloon (perhaps placed upon a nozzle), distends it, knots it, and delivers a distended, knotted balloon.

OBJECT

It is an object of this invention to provide an automatic inflator and knotter for items such as latex balloons, or at least to provide the public with a useful choice.

STATEMENT OF INVENTION

In a first broad aspect, this invention provides apparatus capable of grasping an extendible, flexible cord at a first end and at a second end, and of forming a simple knot between the two ends by means capable of grasping the cord between the first end and the second end, and manipulating the cord according to a predetermined pattern of movements.

Preferably the apparatus is mechanical, powered, and performs a predetermined sequence consistent with mechatronics.

Preferably the predetermined pattern of movements of the mechanical means to form a knot in the cord includes a stretching means, comprising movable means to manipulate the cord so that a portion of the cord is pulled into a loop by virtue of being hooked around a part of the stretching means, and to releasably grip another portion of the neck and pull it through the loop so that a knot is formed.

In a second broad aspect, this invention provides apparatus for accepting latex party balloons having a body and a neck and producing inflated, tied-off balloons, wherein the apparatus includes means to distend the balloon with a charge of gas under a pressure greater than that of air, and mechanical means to then form a knot in the neck of the balloon, so that upon release the balloon retains the charge of gas.

In another aspect the invention provides knot-tying apparatus for knotting a flexible elongate element, including a hook having a shaft lying generally on an axis of rotation and a tangential projection from said shaft, by which in use a first portion of the elongate element can be caught and twisted into a loop by rotation of the hook, said projection including releasable gripping means by which a second portion of said elongate element can be grasped in use, and means to pull the elongate element, and thereby draw the looped first portion over and past the gripping means and the held second portion of the elongate element and thereby form a knot in use.

Preferably the gripping means comprises a pivotally connected pair of jaws tapering to a narrow distal point from a wide rounded base proximal to said shaft.

Preferably the jaws have dished facing edges which can be substantially adjoined to form a cup between them, whereby in use an end of the elongate element can be seated in said cup, such that the looped first portion of the elongate element is capable of being drawn over and past said end when drawn over and past the jaws and the held second portion of the elongate element to form a knot in use.

Preferably at least one said jaw is provided with a detent on an outward edge positioned distally relative to a widest part of said rounded base but proximally relative to said cup.

Preferably the hook is tiltable between a first orientation in which in use a first portion of the elongate element can be caught and twisted into a loop, and a second orientation in which said second portion of said elongate element can be grasped and the elongate element pulled to draw the looped first portion over and past the gripping means and the held second portion of the elongate element, and thereby form a knot in use.

Preferably the knot-tying apparatus further includes a clamp to releasably hold an end of said elongate element, and stretching means movable to draw out the elongate element away from said held end of the elongate element.

Preferably said stretching means is capable of movement in at least two directions, a first direction away from said held end of the elongate element, and a second direction transverse to said first direction to pull the elongate element to draw the looped first portion over and past the gripping means and the held second portion of the elongate element, and thereby form a knot in use.

More particularly the stretching means is moveably mounted on a rail for movement in a first direction, and the rail is in turn moveably mounted on a support body for movement in a second direction substantially orthogonal to the first direction.

Preferably the rail is substantially horizontal such that the first direction comprises a horizontal path, and is moveably mounted on the support body for substantially vertical movement.

Preferably the rail is movable vertically on a rack and pinion.

Alternatively said stretching means is supported on a rotatable arm, in turn supported on one or more translatable platforms together capable of movement in more than one direction.

Preferably the stretching means is movable between a station above the level of the gripping means of the hook and a second station below the level of the gripping means of the hook.

Preferably said stretching means includes a pair of prongs dimensioned and arranged to allow the elongate element to lie between them, whereby in use said prongs can engage with a wider body of said elongate element when moved in said first direction, to draw out the elongate element away from said held end of the elongate element.

Preferably said stretching means further includes a latch at a distal end of one said prong, movable to engage or disengage with a distal end of the other said prong, whereby when engaged in use said latch can pull said elongate element when moved in said second direction to draw the looped first portion over and past the gripping means and the held second portion of the elongate element, and thereby form a knot in use.

Preferably the elongate element comprises the neck of a balloon, and said held end of the elongate element comprises a mouth of said balloon, the apparatus further including a gas vent through which a charge of gas can be provided, said clamp being arranged to releasably hold said mouth on said vent in use.

Preferably said gas vent is provided with a series of nozzles movable between a loading position at which in use a balloon can be mounted on a said nozzle and a discharge position at which in use a charge of gas can be provided through a said nozzle.

Preferably said plurality of nozzles are provided on a rotary spindle. Alternatively said plurality of nozzles are provided in a row on an elongate carrier movable longitudinally from a storage position to a discharge position at which in use a charge of gas can be provided through a said nozzle.

Preferably the apparatus includes means to move the carriers longitudinally, comprising pairs of opposed rollers mounted on a chassis, with means to press one roller of the pair towards the other, and means to drive at least one roller of the pair, wherein the carrier is introduced between the paired rollers in use, and propelled through them.

Alternatively the carrier may move at least in part in a rotary fashion rather than in straight lines. In one version, a balloon selector may move up or down and then rotate. Preferably a plurality of rows of nozzles on at least one said carrier are provided in an array in a support 115 frame, the support frame being movable transversely relative to a direction of said longitudinal movement, whereby in use different said rows can be moved into longitudinal alignment with said discharge position. Preferably a plurality of carriers are provided, movably mounted in a plurality of removable cartridges in turn mounted in said support frame.

Preferably a plurality of carriers are mounted in a parallel series in each said removable cartridge.

Preferably the support frame is moveably mounted on one or more rails extending in a second direction orthogonal to the direction of said longitudinal movement of the carrier, and the rails are mounted on a carriage, which is in turn moveably supported on one or more rails extending in a third direction orthogonal to the first two.

Preferably the knot-tying apparatus further includes an electronic sequencing controller by which the 125 movements of said apparatus are controlled to occur in a predetermined sequence, and by which charges of gas provided through said vent can be controlled to partially or fully inflate a balloon in use. Preferably the knot-tying apparatus further includes a sensor capable of detecting the presence of a balloon at said gas vent.

Preferably said sensor is capable of detecting the colour of a balloon at said gas vent.

Preferably the knot-tying apparatus further includes a sensor capable of detecting the size of a balloon at said gas vent.

Preferably the balloon-loading system includes a control and monitoring system, including: means to detect the position of the support frame; means to monitor nozzles in the support frame to determine which nozzles have balloons mounted on them; means to determine the type of balloon held on a nozzle in the support frame; and control means by which a type of balloon can be selected, and the support frame and carrier can be moved to present a nozzle holding a balloon of that type to the gas supply dock in the balloon-inflating apparatus.

Preferably the means to monitor the nozzles in the support frame includes a sensor adapted and arranged to detect the presence or absence of a balloon on a nozzle.

Preferably the sensor is also adapted and arranged to distinguish the colour of a balloon on a nozzle.

Alternatively the means to monitor the nozzles in the support frame includes a counter, which can record the number of times a row of nozzles has been moved into alignment with the gas supply dock.

Preferably the control and monitoring system further includes means to monitor the supply of a gas for inflation of the balloons.

Preferably the control and monitoring system further includes a display means, by which an operator can be advised of the numbers and types of balloons held in the support frame.

Preferably the control and monitoring system further includes data input means with the display means, by which, when in use, an operator can specify a type of balloon to be selected.

Preferably the control and monitoring system includes a remote display means, by which an operator can be advised of the numbers and types of balloons held in the support frame remotely.

In a further broad aspect the apparatus includes a set of actuators capable of causing movement of the mechanical means.

Preferably the actuators are selected from the range of electrically powered; pneumatically powered, or mechanically powered actuators; of one or a combination of types.

Optionally the actuators have their effect on the mechanical means for gripping the balloon through levers, and as a further option, rotation of stepped cams may be used to cause movements in a sequence.

Optionally the sequencing controller includes means to cause balloons to be inflated to a predetermined size.

Preferably the means includes a mechanical sensor positionable to be contacted by the wall of a balloon when inflated by the apparatus.

Preferably the knot-tying apparatus further includes at least one gas cylinder from which said charge of gas can be provided in use.

Alternatively the apparatus includes a compressor to compress air.

Preferably the knot-tying apparatus is slidably mounted in an outer protective casing, such that it can be raised vertically out of the casing in use and the casing forms a base on which the apparatus stands.

Preferably the apparatus is moved relative to the casing by an electrical actuator and a belt drive system.

Alternatively the apparatus is moved relative to the casing by an electrical actuator and a rack and pinion system.

In another aspect the invention provides method for tying the neck of a balloon having a mouth, a neck and an inflatable body, comprising the steps of:

clamping said mouth of the balloon onto a gas vent; at least partially inflating the body of the balloon with a charge of gas supplied through said gas vent; engaging the body of the balloon with stretching means, and moving said stretching means away from the clamped mouth to extend the neck of the balloon: moving a hook to catch the neck of the balloon, said hook having gripping means at a distal end thereof; rotating said hook to twist a first portion of the neck into a loop; tilting said hook to catch a second portion of the neck with said gripping means; moving said hook and said stretching means apart, so as to draw said looped first portion of the neck off the hook and past the gripped second portion of the neck, to form a knot;

and releasing said gripping means to release said balloon.

Preferably the second portion of the neck of the balloon is between the loop and the mouth of the balloon, and the method further includes the step of releasing the clamp at the mouth of the balloon after closing the jaws to grip the second portion of the neck, such that the mouth of the balloon can be drawn through the loop with the second portion of the neck to form a knot.

PREFERRED EMBODIMENT

The description of the invention to be provided herein is given purely by way of example and is not to be taken in any way as limiting the scope or extent of the invention. Throughout this specification unless the text requires otherwise, the word “comprise” and variations such as “comprising” or “comprises” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

This specification describes a “work in progress”. The invention may comprise only a component—even though it is a critical component—of a complete machine. Further developments may involve the use of alternative, perhaps ingenious mechanisms to cause similarly effective movements for the purposes of optimisation of weight, size, cost and complexity, for example. Nevertheless the invention to be described below does inflate and knot balloons quickly and reliably.

DRAWINGS

FIG. 1 a and b: show a balloon inflating apparatus of this invention in a functioning and in a storage configuration respectively.

FIG. 2: schematically illustrates the components of the apparatus of FIG. 1.

FIGS. 3 a to 3 m: (over 2 sheets) illustrate in sequential steps the operation of the apparatus of this 200 invention.

FIGS. 4 a and 4 b: show detail of the jaw components of the hook, in side section and from above respectively.

FIG. 5: is a schematic illustration of a knotter, stretcher and inflator of the invention, in combination with one type of balloon-supply apparatus and a control system.

EXAMPLE 1

This embodiment of the invention relates to a balloon knotting machine which is an automatic machine for holding, filling and then securely knotting (using a simple, overhand knot; not a loop) ordinary latex party balloons. It is intended for preparation of a quantity of distended balloons rather than a maximum of 10 or 20 as for a domestic event. The machine uses “mechatronics”; an art making use of electric, hydraulic or pneumatic actuators as motors; levers, pivots, slides, clamps and the like, a mounting frame, and a digital or similar processor to provide a controlled sequence of actions (a “state machine”) in order to carry out the specific function required. The particular embodiment to be described was at least partly intended as a test-bed for sequence control and to ascertain the properties required of individual parts. At the time of filing, this embodiment is not optimised for low cost, low weight, and other desirable attributes as can be realised with ingenious mechanisms and purpose-built actuators and components.

As the reader will appreciate, tying a knot in a material without use of mechanical aids or human intervention requires a certain amount of robotic dexterity, especially if the material is a latex tube that should be held closed and sealed during the tying process because there is an already inflated balloon at one end of it. The balloon knotting machine or knot-tying apparatus to be described here incorporates three active devices, each having holding means and actuators that manipulate the balloon, namely:

(A) a two-part clamp 30 which clamps the mouth 60 b and neck 60 a of a balloon (see FIG. 3) on the filling nozzle 14 at the position 14 b, (B) a first stretching means 40 comprised of a pair of prongs or fingers which stretch the neck of the balloon downwardly from the clamped mouth at the nozzle 14 b, and (C) a second stretching means 50 comprised of a hook with a closable jaw component at the distal end, on a mount rotatable about axle 55 which in use catches the neck of the balloon between the nozzle and the first stretching means, twists it into a loop and pulls the mouth of the balloon through the loop to tie a knot.

During operation the elastic neck of the balloon 60 being tied is held on one end at a filling nozzle 14, at the other end by a support 40 resting against the inflated body of the balloon, while a third mechanism 50 operating in a space near the middle of the neck and having closable jaws engages with the balloon neck to form a loop, which is converted into a knot by release of the mouth of the neck from the nozzle while the jaws close and the orientation of the jaws moves, relative to the support 40, in order to allow the knot to be pulled off the jaws as they open again.

As shown in FIG. 1, this embodiment of this invention preferably comprises a small unit 10 about 1 metre in height and this example when closed down can retract into a low case as shown in FIG. 1 b and which is preferably mobile or semi-mobile, so that it can be installed in different locations and/or taken to events to inflate balloons at the site. The nozzles 14 of the machine are sequentially loaded with balloons manually, by an operator or a customer. The unit 10 includes a control panel 11 by which the operation of the apparatus is controlled, and may have wheels or casters 12 on which it can be moved.

The unit 10 may optionally include one or two more nozzles 13 on the exterior, which are connected to a gas supply and can be used for inflation of balloons outside the apparatus, for example for inflating balloons which are too large to be inflated in the apparatus. These balloons can then be knotted or clipped manually. Because the tying process is manually difficult and time-consuming, the unit 10 is more preferably used to tie balloons automatically, as described hereafter.

An operator loads a selected balloon 60 into the apparatus by slipping the mouth 60 b and outermost part of the neck 60 a of the balloon over a nozzle 14, that is visible and accessible through a hatch 15 in the casing 16 of the unit. The frame of the hatch 15 is provided with a laser curtain 17 or other proximity-sensing means capable of reliably detecting the presence of the operator's hands passing into the unit, and possible concurrent operation of the apparatus paused for safety reasons. The operation of the apparatus can be started with use of the control panel 11, or alternatively may commence automatically when the laser curtain 17 detects that the operator's hands have been withdrawn and the hatch is clear.

When the apparatus has inflated and tied a balloon 60, the finished balloon is ejected through a second hatch 18, to be caught and collected manually. If the balloons are inflated with helium or otherwise liable 255 to escape, a net may be positioned around and/or above the hatch 18 to catch them as they exit the unit 10.

As shown in FIG. 1 b, this option of the unit is collapsible, with an upper part 10 a in which most of the mechanism of the apparatus is housed. Part 10 a is able to slide down into a lower part 10 b, which then forms a protective outer casing for transport. The hatch 18 in the lower part is preferably provided with a door or flap 19 by which it is closed while the unit is in transit. A lid (not shown) is preferably also provided to protect the top of the unit 10. The upper part is preferably raised and lowered electronically by a mechanism controlled from the control panel 11, best seen in FIG. 2.

As shown in FIG. 2, the upper part 10 a of the unit fits slidably within the lower part 10 b, and is connected to vertical belts 20, driven by a motor 21. By operating the motor in forward or reverse from the control panel 11, the belt can be moved in either direction to raise or lower the upper part 10 a within the lower part 10 b. That raising/lowering option is unrelated to the primary knot-tying purpose of the machine.

The inflation and tying apparatus of the unit are shown in more detail in FIG. 2.

The unit usually houses or is attached to one or more gas cylinders 22 containing gas for inflation of balloons, connected via the usual valves including solenoid valves and regulators (not shown) through gas conduits 23 to a gas supply spindle 24 on which four nozzles 14 are mounted, and also (if present) to the exterior nozzles 13. If two or more cylinders are provided, different cylinders may contain different gases, in particular helium and compressed air, which are carried along separate supply lines (not shown). Alternatively or additionally the unit could be provided with a connector for connecting to a compressor, by which air can be compressed and supplied through the nozzles to fill balloons. In the prototype at this time use of a compressor creates an initial high-pressure burst when first starting to fill a balloon, which sets up a high frequency vibration in the balloon as it inflates, causing an unpleasant level of noise. Compressed air supplied from a cylinder does not create an initial high pressure burst, perhaps as a result of pressure regulator action, and the smoother air flow results in quieter filling. This may be a side-effect of seeking to raise the throughput of the machine. Noise may also be overcome with the use of means such as an adjustable needle valve, or acoustic control by localised or distributed damping means within the supply line to the nozzle.

The gas supply spindle 24 is mounted on an axle 25 angled at 45° off vertical, and has four nozzles 14 projecting radially and at 45° to the axis of rotation, such that by rotating the spindle 24 through an angle each nozzle can be moved in turn from a position at which it is projecting horizontally (14 a) for access by the operator through the hatch 15, to a position at which it is projecting vertically downward (14 b) to facilitate access by the knot-tying apparatus below. Four nozzles is a convenient number (at least for this prototype) but other numbers may be used.

Release of gas and proper sequential operation of the apparatus are controlled by a digital microprocessor (CPU 26) (including pre-programmed memory and the usual power supply and supporting devices) also contained within the unit although an external lap-top is used during development. The demands made by the software and desired operation speed on microprocessor capability are not great. A state-machine diagram (Table 1) describes the functions of the CPU, at least in regard to producing a filled and knotted balloon. For clarity, control links (wiring) between the CPU, the control panel 11 and the various components of the apparatus such as sensors and actuators are omitted in the drawings since they will be apparent to those skilled in the mechatronics arts.

The three components (A), (B), and (C) of the knot-tying apparatus will be described in more detail.

The two-part clamp 30 is comprised of two pivotally-mounted arms 31 each having a vertical half-pipe 32 formed at the distal end, so that when the two arms 31 are swung together by an actuator 36, the two half-pipes 32 together clamp entirely around the nozzle 14 at the position 14 b, and the mouth of a balloon mounted on that nozzle. As shown here, the arms 31 may conveniently be made symmetrical with two opposing half-pipes 32, so that identical components can be used for both sides of the two-part clamp 30.

The first stretching means is comprised of two parallel horizontal rods 41 and 42. A latch 43 is provided on the end of one rod 41, which can swing to engage or disengage from the end of the other rod 42, actuated by a motor 44. The rods 41 and 42 are mounted on a body 45, in turn mounted on a rail 46 parallel to the rods, so that the rods can be moved longitudinally by moving the body 45 along the rail. The rail 46 is in turn mounted on a vertical rack 47 engaged with an actuated pinion 48, by which the rail can be raised and lowered vertically.

The second stretching means 50 has a hook formed at the end of a shaft. The hook portion is comprised of a pair of closable jaws 51 (see FIG. 3) formed as smoothly tapered fingers projecting at about 80° from a rotational axis at the base. The jaws 51 are mounted on the end of the shaft 52, and can be rotated about the axis by a motor 53 acting through a belt drive 54. This hook assembly is all mounted on a horizontal pivot axle 55 on a carriage 56, such that the hook assembly can be tilted relative to the carriage 56 between an orientation as shown in FIG. 2 where the shaft 52 is substantially vertical, and an orientation (as FIG. 3 f) where the shaft 52 is substantially horizontal.

The carriage 56 is in turn mounted on a horizontal rail 57 which extends at an angle of about 30° to 60° to the pivot axle 55 of the hook assembly. An actuator 58 is provided to drive the carriage 56 back and forth along the rail, whether by means of a ram, a rack and pinion mechanism or other means.

Operation of the example knot-tying mechanism, reduced to control of 11 parts named across the top, is summarised as a list of sequential states in the following table, Table 1:

Drive Knotting Loading Base tube head disc Inflation Horizontal Swing Vertical Slider rotation rotation State Description rotation arm Gripper Inflate slide (mm) clamp slide (mm) (mm) (deg) (deg) Jaws 1.0 Place balloon off extend open off 0 open 0 0 0 0 open 2.0 Release loading disc off retract open off 0 open 0 0 0 0 open 2.1 Index loading disc on retract open off 0 open 0 0 0 0 open 2.2 Lock loading disc off extend open off 0 open 0 0 0 0 open 3.0 Grip balloon lip off extend close off 0 open 0 0 0 0 open 3.1 Clamp neck off extend close off h1 open v1 0 0 0 open 3.2 Inflate Balloon partial off extend close on h1 open v1 0 0 0 open 3.3 Stretch neck off extend close off h1 open 0 0 0 0 open 3.4 Close Swing Clamp off extend close off h1 close 0 0 0 0 open 3.5 Inflate Balloon fully off extend close on h1 close 0 0 0 0 open 4.0 Move Base Slider off extend close off h1 close 0 s1 0 0 open 4.1 Close jaws off extend close off h1 close 0 s1 0 0 close 4.2 Rotate Drive Tube off extend close off h1 close 0 s1 270 0 close 4.3 Open jaw off extend close off h1 close 0 s1 270 0 open 4.4 Rotate Drive Tube off extend close off h1 close 0 s1 0 0 open 4.5 Position Base Slider (reverse) off extend close off h1 close 0 s2 0 0 open 4.6 Lift up Knotting Head off extend close off h1 close 0 s2 0 90 open 4.7 Close jaws off extend close off h1 close 0 s2 0 90 close 4.8 Open Gripper off extend open off h1 close 0 s2 0 90 close 4.9 Retract Neck Stretcher off extend open off 0 close 0 s2 0 90 close 4.10 Open jaws off extend open off 0 close 0 s2 0 90 close 5.0 Set starting positions off extend open off 0 open 0 0 0 0 open

Many of the following 13 Figures that together comprise FIG. 3 have been drawn from single frames of video sequences. As shown in FIG. 3 a, the process begins with an uninflated balloon 60 with a neck 60 a and a mouth 60 b mounted on a nozzle 14 rotating by two stages from the position 14 a at which it was placed on the nozzle by the operator, to position 14 b at which it hangs vertically from the downwardly 325 extending nozzle. Most “party” latex balloons have a standardised neck diameter.

As shown in FIG. 3 b, the clamp 30 is closed on the neck 60 a and mouth 60 b of the balloon, clamping and holding it on the nozzle 14. The first stretching means 40 is moved vertically to be positioned above the bulb of the balloon, in alignment with the neck.

As shown in FIG. 3 c, the first stretching means 40 is then moved longitudinally towards the balloon so that the parallel prongs 41 and 42 extend past both sides of the neck 60 a of the balloon 60. The balloon 60 is then at least partially inflated. As shown in FIG. 3 d, the first stretching means 40 is then moved downwardly to stretch the neck of the balloon. The latch 43 is rotated and closed onto the end of the prong 42 to encircle the neck of the balloon, and the balloon can be fully inflated.

As shown in FIG. 3 e, the hook assembly of the second stretching means 50 is moved diagonally through the vertical line of the stretched neck above the first stretching means 40 and below the clamp 30, to catch the neck 60 a (which is in a predictable position) and stretch it out diagonally to one side. At this stage the hook assembly is canted up slightly from a horizontal orientation. The jaws are open. As shown in FIG. 3 f, the jaws 51 on the end of the hook assembly are then rotated to catch and pull the neck portion under the rotational axis of the shaft 52, and the assembly is tilted down to lie substantially horizontal.

As shown in FIG. 3 g, the jaws continue to rotate, taking the neck portion below the rotational axis of the shaft 52 around and up to cross over the portion above, forming a loop as shown in FIG. 3 h. As shown in FIG. 3 i, the hook assembly of the second stretching means 50 is then tilted up while the jaws are held open, such that the jaws pass on either side of a portion of the neck above the loop which has just been formed, until the hook assembly is in a vertical orientation as shown in FIG. 3 j. At this point the loop in the balloon neck will slip off the back of the jaws 51 and ride along the sides until it reaches detents 70 (see in FIG. 4 a or 4 b).

As shown particularly in FIGS. 4 a and 4 b, the jaws 51 taper from a wide base 51 a around the shaft 52, to a narrow distal point 51 b. The jaws meet along inside edges 51 c, the upper faces of which are dished so that together they form a cup 71 in the upper surface. The outer edges of both jaws are provided with detents 70, or outward projections at a point between the wide base 51 a and the main part of the jaw forming the cup 71. The detents 70 prevent the loop in the neck from sliding directly off the wide base part 51 a and riding further along the jaws 51 into contact with the stretched portion of the neck passing between the jaws, extending upwardly to the mouth 60 b held on the nozzle by the clamp 30.

As shown in FIG. 3 k, the jaws 51 are closed to clamp onto the portion of the neck passing between them, and the clamp 30 is then opened to release the mouth 60 b of the balloon. The mouth of the balloon slips off the nozzle under the tension provided by the stretched neck 60 a, and seats down into the cup 71 (best seen in FIG. 4) formed in the top surfaces of the jaws 51.

As shown in FIG. 31, the first stretching means 40 then moves longitudinally away from the hook assembly of the second stretching means. The latch 43 pulls on the neck portion below the loop, pulling 360 the loop past the detents 70 and over the mouth of the balloon seated in the cup 71. The loop slides along the smoothly tapered jaws 51 and off the distal end, thereby completing a tight, sealing knot 60 c.

As shown in FIG. 3 m, the jaws 51 are then opened to release the mouth of the balloon, and the balloon 60 springs away, to fall out the hatch 16 or be pushed out by the next balloon inflating.

Balloon Loading

Clearly the utility of the above knotter will be improved by automation of the balloon loading aspects as well. Loading automation will allow “coin-operated machine” applications in which a user puts money in a slot, presses a selection button, and gets a distended balloon, ready to use; helium or air. It also allows a person preparing balloons for a big event to delegate inflation and knotting to a machine which will work at a rate exceeding that of several human workers. Automation may allow a manufacturer to make and sell pre-loaded magazines.

FIG. 5 schematically illustrates one version of a balloon supply and loading system of the invention, in combination with a second filling and tying apparatus of the general type described above. The tying apparatus is shown at the point at which a balloon 200 has been inflated with helium or other gas from a cylinder 201, the mouth of the balloon has been released from the nozzle 130 by the clamps 131, the neck of a balloon 200 has been formed into a loop around the jaws 113, 114 (which also still hold the mouth of the balloon), and the paired rods 125, 126 are about to pull the bulb of the balloon 200 away, so that the loop in the neck is drawn off the jaws 113, 114, over the mouth, and thereby forms a knot. This is step 31 in the tying sequence described above. Note that the first stretching means 123 differs from the stretching means 40 described above, in that the rods 125 and 126 have no latch and are arranged to pull sideways through a rotary action of the body 123. This arrangement is less preferred than the mechanism described above, but constitutes a possible alternative arrangement within the scope of the invention.

As shown in FIG. 5, the balloon supply and loading system in this embodiment includes an array of deflated balloons already mounted (perhaps at a factory) on an array of nozzles 130. This can provide an advantage over a single nozzle system, as described above, in that the nozzles 130 provide a consistent 385 shape and form which other parts of the apparatus can reliably engage with, although the balloons themselves often do not. A row of nozzles 130 are mounted on an elongate, substantially inflexible strip 202, and a horizontal series of these strips are mounted in parallel slides in a cartridge 203. A vertical stack of cartridges 203 are in turn held within a support frame or cabinet 204, to provide a three dimensional array of nozzles held in the support frame 204, with balloons mounted on them. In practice it is preferred that each strip 202 is fitted with a row of balloons 200 of the same type and colour, and different strips 202 or cartridges 203 may be fitted with balloons of different types and colours.

To select a balloon for inflation of a particular type or colour, the entire support frame 204 is moved (as described below) so as to align an appropriate strip 202 with the gas supply dock 205. The gas supply dock 205 comprises a station at which an outlet from the helium cylinder 201 (or other gas supply) is arranged to be engageable with the top of a nozzle 130, so as to supply gas through it.

When the appropriate strip 202 is in alignment with the gas supply dock 205, a roller assembly 206 is moved into engagement with the end of the strip 202. The roller assembly 206 comprises vertical pairs of rollers mounted on a chassis, with springs on the lower roller to press the two together, and a motor drive on the upper roller. The pairs of rollers grip the end of the strip, and impel it through them, to draw it out of the cartridge 203 and project it past the gas supply dock 205. If some balloons have already been taken from the strip, the strip is impelled further, and the empty nozzles 130 are moved beyond the gas supply dock, until a nozzle which still carries a balloon 200 arrives. Then the roller assembly 206 is stopped, the gas supply is engaged with that nozzle, and the inflation process can begin. When the balloon has been inflated, tied and dispensed, the roller assembly 206 can either impel the strip 202 further to allow the next balloon in line to be inflated, or return the strip 202 to the cartridge 203 by running in reverse.

To allow movement of the support frame 204 and the arrays of balloons held within it, the frame is preferably mounted on runners 207. By this means the support frame 204 can move from side to side on horizontal rails 208, to allow any particular strip 202 in each cartridge to be aligned with the roller assembly 206 and the gas supply dock 205. The horizontal rails 208 are in turn mounted on a carriage assembly 209 which is able to be run up or down on vertical rails 210, so that any cartridge 203 in the vertical stack can be brought into line with the roller assembly and gas supply dock.

Operation of the balloon supply system is preferably controlled by a central processing unit (CPU 211), which takes input from a range of different sensors, and controls the operation of various mechanical or electronic actuators required to position the different parts of the apparatus in the correct place at the correct time. The unit 211 may also be the sequencing controller used for the tying apparatus described above.

The sensors will preferably include a mechanically actuated sensor 212 which can be positioned to be contacted and actuated by the inflated balloon 200 when it reaches a specific diameter, so that inflation can be halted and the tying process started. By this means the balloons can be inflated to a consistent size, regardless of variations in wall thickness or elasticity, which can be of advantage when the balloons are used for sculpture or mass display.

A photosensor 213 is preferably used at the gas supply dock 205, to detect a balloon on a nozzle 130, so as to distinguish those nozzles which still have balloons attached from those which are empty, and to confirm that the balloon is in place before actuating the gas supply dock 205.

Further photosensors 214 (only one illustrated) are preferably used at the back of the support frame 204, to distinguish empty strips 202 from those which still carry at least one balloon, and preferably also to inform of the colour and/or type of balloon held on a particular strip, unless colour or type is predetermined or readable for example from a barcode-like coded label attached to each strip.

By this means, a display screen 215 on the apparatus can be used to advise an operator of the machine which colour choices are still available in the machine and which are not. The display screen 215 preferably includes data entry means, whether keyboard, buttons, a touch-sensitive screen or other such means, so that the operator is also able to submit instructions to the apparatus through the unit 211.

Preferably the central processing unit 211 can also supply information over a communications link to a remote monitor 216, so that maintenance and resupply of balloons to a number of different machines can be managed and co-ordinated remotely. In particular in this case, it may be desirable for a further sensor 217 to be connected with the gas cylinder 201, so that the gas supply can also be monitored and managed remotely.

Finally, further sensors 218 and actuators are provided on the carriage 209 and support frame 204 to confirm and control movement and positioning, and similarly control systems (not illustrated) will be used to allow the knotting apparatus to be co-ordinated with the other parts of the apparatus, through the central processing unit 211.

The control system may further include means to price, barcode, receipt and/or facilitate electronic funds transfer, to suit use of the apparatus for retail purposes. In such a case the apparatus will be enclosed in a housing, with sufficient clearance to allow movement of the support frame 204, the strips 202 and other parts of the apparatus as described above. The gas cylinder 201 would in a retail environment preferably be kept remote for safety reasons, and gas would be supplied to the apparatus through a hose, with monitoring and control still co-ordinated through the central processing unit 211.

Apparatus used in a retail environment might also include catching and bundling systems, utilising nets, bags and/or ribbon-ties.

It is envisaged that the strips and/or the cartridges may comprise reusable units, supplied with the balloons and returned to the manufacturer when empty. Alternatively they might be disposable units, or could be restocked with balloons by an operator of the machine. The balloons might also be supplied with ribbons. If an end of the ribbon is inserted into the neck of the balloon or adhered onto it, it can be stretched out, looped and tied along with the neck of the balloon, to provide a secure fastening without additional equipment or action being required in the apparatus. The ribbon could be supplied in a roll, to avoid tangling.

Alternatively, with a single-nozzle system, balloons could be supplied ready for automated loading in a magazine form perhaps comprised of a stout paper tape (180 gsm or equivalent) of indefinite length that is made with a series of holes along its length. Each latex balloon is mounted on one side of the tape with the neck of the balloon protruding through the hole. The hole is preferably tearable for facilitated removal. The filled tape can be sold in reels. This system provides that an indefinite number of balloons can be presented to a machine in a precise and repeatable position. Additional hardware for the invention comprises (a) means to remove each balloon from the tape in sequence, and (b) means to transfer each balloon onto the nozzle 130 ready for inflation. The preferred transfer means comprises a group of three or four wire or metal rod probes capable of three actions: (1) lateral translation, (2) forwards and backwards translation, and (3) spreading apart from a common axis and returning to a close-together configuration. Step 1 has the group approach by lateral translation a tape holding balloons; the next balloon being held at a consistent position. Step 2 is forwards translation into the aperture of the open neck of the balloon. At this point the probes spread apart. Step 3 is lateral translation to break the tape and remove the balloon by its neck. Step 4 completes lateral translation to a point over the nozzle 130. Step 5 is backwards translation of the group to surround the nozzle. At this point the group partly comes together so that the neck primarily grips the nozzle 130 and the group of probes are completely withdrawn. Now the previously described filling and knotting process can begin. A balloon artist can glue or staple short lengths of balloon-bearing tapes together according to colour in order to make a variety of colours.

Reference to orthogonal movements is in accordance with one example. In another version, the carrier may move at least in part in a rotary fashion rather than in straight lines. For instance, a balloon selector may move up or down and then rotate in order to access one of many selection points in a movement reminiscent of the Strowger switches once used in telephone exchanges.

Variations

The machine is generally suited to form a knot near one end of a stretchy balloon neck because the present design assumes that the free end will (at about the stage shown in FIGS. 3 k-31) fly off the nozzle and be held in the cavity 71 formed in the jaws. Modifications may permit a serviceable knot to be formed along the length of an extended cord-like structure.

A modification will allow the inclusion of a string or tape for attachment to the distended balloon, to hold on to it. That accessory need not be used in the formation of the knot, unlike many prior-art strings.

It should be noted that a wide variety of changes could be made to the structural details of the apparatus as described above, within the general scope of the invention. In particular, the form and arrangement of parts may be altered considerably to suit use in a retail environment, supplying a large number of customers with relatively small and varied orders, or to suit a professional operator, requiring large numbers of the same or similar balloons. There may be a requirement for use of advanced materials in the construction of the jaws 113 and 114 in order to overcome requirements for strength and long-term wear resistance, while all other parts are conventional.

Movements could for example involve use of levers and pantograph-type movements, perhaps using drives based on cams, or other alternatives such as solely rotary actuators with side arms that swing other parts around, rather than the rails and sliders shown here in combination with both linear and rotary actuators. Some suitable forms of combined linear and rotary actuators may resemble the action of Strowger switches as formerly used in telephone exchanges.

Actuators and sequencers could be pneumatic, or a mixture of electric and pneumatic actuators. The presence of compressed air in the machine for balloon distension facilitates use of pneumatic devices; also a need for possibly dangerous electric power is removed and the machine can be run without mains electricity in the back of a van at a site. (12 volt power is of course a usable option). It would be uneconomic to run pneumatic actuators on bottled helium so separate balloon gas and actuator gas circuits may be needed.

Balloons made of some materials other than latex, or balloons having only a neck portion made of latex, may be used with the machine, and other elongate materials may be tied near one end.

INDUSTRIAL APPLICABILITY AND ADVANTAGES

The invention supplies a long-felt need in the balloon decorating industry. Anyone (such as a certified balloon artist) who blows up and ties off more than about 100 balloons a day will appreciate mechanical assistance, consistency of results, and the increased speed that accompanies it, and will be able to concentrate on the artistic aspects of a decorating task.

This machine does not need any special sealing devices, whereas some prior art uses clips or other seals. The prototype machine can complete distending and knotting of one balloon in about 1 to 2.5 seconds and production machines may be faster if optimised.

This machine provides actions which are all highly feasible in engineering terms. For example there are no flexible Bowden cables to carry drives around corners nor can parts collide with each other even if the sequence controller breaks down.

The invention may be used to provide an automated balloon supply in a retail environment, whereby specific selections of balloons can be ordered by customers of the retailer, and automatically inflated to order. Other possible applications include the sealing bags of food or other commodities.

The process may be adapted for adapted for robotic knot-tying in surgery or in the manufacture of items such as footballs or shoes.

Finally, it will be understood that the scope of this invention as described and/or illustrated herein is not limited to the specified embodiments. Those of skill will appreciate that various modifications, additions, known equivalents, and substitutions are possible without departing from the scope and spirit of the invention as set forth in the following claims. 

1. Knot-tying mechanical apparatus employing mechatronics for forming a knot near an end of a flexible elongate element (60 a), characterised in that the apparatus includes releasable means (14 with 30), and means 40 to hold a length of the flexible elongate element in tension during a knotting process across a space near to a hooking mechanism having a rotatable shaft (52) and a tangential projection or hook (51, 51) extending from said shaft; the hooking mechanism being capable of moving within the space in order to make contact with a first portion of the elongate element then of twisting the first portion into a loop by rotating the hook, said hook including releasable gripping means capable of grasping a second portion of said elongate element and then orienting the second portion towards holding means 40; meanwhile releasing the releasable means, and means (40) to pull one end of the elongate element, and thereby draw the looped first portion over and past the gripping means and the held second portion of the elongate element; and thereby forming a knot (60 c) in use.
 2. Knot-tying apparatus as claimed in claim 1 adapted for inflating and then sealably tying a latex rubber balloon, characterised in that the apparatus includes: a hook (51, 51) having a shaft (52) lying generally on an axis of rotation and a tangential projection (51) from said shaft, by which in use a first portion of the elongate element (a neck of the balloon) can be caught and twisted into a loop by rotation of the hook, said projection including releasable gripping means by which a second portion of said elongate element can be grasped in use; and means (40) to apply tension to the elongate element, and thereby draw the looped first portion over, and past the gripping means and the held second portion of the elongate element and thereby form a knot (60 c) in use.
 3. Knot-tying apparatus as claimed in claim 2, characterised in that the gripping means comprises a pivotally connected pair of jaws (51) tapering to a narrow distal point (51 b) from a wide rounded base (51 a) proximal to said shaft (52).
 4. Knot-tying apparatus as claimed in claim 3, characterised in that the jaws have dished facing edges (51 c) which can be substantially adjoined to form a cup (71) between them, whereby in use an end (mouth 60 b) of the elongate element can be seated in said cup, such that the looped first portion of the elongate element is capable of being drawn over and past said end when drawn over and past the jaws (51) and the held second portion of the elongate element to form a knot in use.
 5. Knot-tying apparatus as claimed in claim 4, characterised in that at least one said jaw (51) is provided with a detent (70) on an outward edge positioned distally relative to a widest part of said rounded base (51 a) but proximally relative to said cup (71).
 6. Knot-tying apparatus as claimed in claim 2, wherein the hook is tiltable between a first orientation (FIG. 3 e) in which in use a first portion of the elongate element can be caught and twisted into a loop, and a second orientation (FIG. 3 j) in which said second portion of said elongate element can be grasped and the elongate element pulled to draw the looped first portion over and past the gripping means (51) and the held second portion of the elongate element, and thereby form a knot in use.
 7. Knot-tying apparatus as claimed in claim 2, characterised in that the apparatus further includes a clamp (30) to releasably hold an end of said elongate element (FIG. 3 b), and stretching means (40) movable to draw out the elongate element away from said held end of the elongate element (FIG. 3 d).
 8. Knot-tying apparatus as claimed in claim 7, characterised in that said stretching means (40) is capable of movement in at least two directions, a first direction away from said held end of the elongate element (FIG. 3 d), and a second direction transverse to said first direction to pull the elongate element (FIG. 31) to draw the looped first portion over and past the gripping means (51) and the held second portion of the elongate element, and thereby form a knot in use.
 9. Knot-tying apparatus as claimed in claim 8, characterised in that said stretching means (40) includes a pair of prongs (41, 42) dimensioned and arranged to allow the elongate element (60 a) 575 to lie between them, whereby in use said prongs can engage with a wider body of said elongate element when moved in said first direction, to draw out the elongate element away from said held end of the elongate element (FIG. 3 d).
 10. Knot-tying apparatus as claimed in claim 9, characterised in that said stretching means (40) further includes a latch (43) at a distal end of one said prong (41), movable to engage or disengage with a distal end of the other said prong (42), whereby when engaged in use said latch can pull said elongate element when moved in said second direction (FIG. 31) to draw the looped first portion over and past the gripping means (51) and the held second portion of the elongate element, and thereby form a knot in use.
 11. Knot-tying apparatus as claimed in claim 7, characterised in that the elongate element (60 a) comprises the neck of the balloon (60), and wherein said held end of the elongate element comprises a mouth (60 b) of said balloon, the apparatus further including a gas vent (14) through which a charge of gas can be delivered from a controlled supply of gas, said clamp being arranged to releasably hold said mouth on said vent in use.
 12. Knot-tying apparatus as claimed in claim 11, characterised in that the apparatus includes a sequencing controller by which (A) the movements of said apparatus are controlled to occur in a predetermined sequence, and (B) the charge of gas provided through said vent can be controlled to partially or fully inflate a balloon in use.
 13. Knot-tying apparatus as claimed in claim 12, characterised in that a state diagram embodies the predetermined sequence used by the sequencing controller.
 14. Knot-tying apparatus as claimed in claim 12, characterised in that said gas vent is provided with a series of nozzles (14) movable between a loading position (14 a) at which in use a deflated balloon can be mounted on a salt) nozzle and a discharge position (14 b) at which in use a charge of gas can be provided through a said nozzle.
 15. Knot-tying apparatus as claimed in claim 11, characterised in that said plurality of nozzles (14) are provided on a rotatable spindle (24).
 16. Knot-tying apparatus as claimed in claim 11, characterised in that a plurality of said nozzles (130) are provided in a row on an elongate carrier (202) movable longitudinally from a storage position to a discharge position at which in use a charge of gas can be provided through a said nozzle.
 17. Knot-tying apparatus as claimed in claim 16, characterised in that a plurality of rows of nozzles on at least one said earlier (202) are provided in an array in a support frame (204), the support frame being movable in a flat or a curved plane relative to a direction of said longitudinal movement, whereby in use different said tows can be moved into longitudinal alignment with said discharge position.
 18. Knot-tying apparatus as claimed in claim 15, characterised in that a plurality of carriers (202) are provided, movably mounted in a plurality of removable cartridges (203) in turn mounted in said support frame (204).
 19. Knot-tying apparatus as claimed in claim 17, characterised in that a plurality of carriers (202) are mounted in a parallel series in each said removable cartridge (203).
 20. Knot-tying apparatus as claimed in claim 18, characterised in that the apparatus includes a control and monitoring system, having at least one of: (a) means (218) to detect the position of the support frame; (b) means (214) to monitor nozzles (130) in the support frame to determine which nozzles have balloons mounted on them; (c) means to determine the type of balloon held on a nozzle in the supports frame; and (d) user control means (211, 215) by which a type of balloon can be selected, so that the support frame and carrier can be moved under system control to present a nozzle holding a balloon of that type to the gas vent (205) in the balloon-inflating apparatus.
 21. Knot-tying apparatus as claimed in claim 15, characterised in that the apparatus further includes at least one of: (a) sensing means (213) capable of detecting the presence of a balloon (200) at said gas vent (205); sensing means (213, 214) capable of detecting the colour of a balloon (200); sensing means (212) capable of detecting the size of a balloon (200); sensing means (217) to monitor a supply of gas at a pressure, from a compressor or a tank or a cylinder, for inflation of the balloons.
 22. Knot-tying apparatus as claimed in claim 21 characterised in that the control and monitoring system further includes at least one display means, by which a nearby (215) or a remote (216) operator can be advised of the numbers and types of balloons held in the support frame.
 23. Knot-tying apparatus as claimed in claim 11, characterised in that the apparatus is slidably mounted within a protective casing (10 b), such the it can be raised out of the casing when in use and the casing forms a base on which the apparatus stands.
 24. A method for tying an extensible cord near one end using apparatus as claimed in claim 1, characterised in that the method comprises the steps of: clamping a first, end portion of the cord; then clamping a second portion of the cord extending an intermediate portion of the cord: moving a hook to catch the intermediate portion, said hook having gripping means at a distal end thereof and then rotating said hook to twist a first portion of the intermediate portion into a loop; tilting the hook to catch a second portion of the intermediate portion by closing the gripping means; moving said hook anti said stretching means apart, so as to draw said looped first portion of the intermediate portion off the hook and past the gripped second portion of the intermediate portion, to form a knot during which phase the first end is released; and releasing said gripping means to release said extensible cord.
 25. A method according to claim 24 adapted for distending, then tying the neck of a balloon having a mouth, a neck and an inflatable body, characterised in that the method comprises the steps of: clamping the mouth of the balloon on to a controlled gas vent; at least partially inflating the balloon with a charge of gas; engaging the body of the balloon with stretching means, and moving said stretching means away from the clamped mouth to extend the neck of the balloon: moving a hook to catch the neck of the balloon, said hook having gripping means at a distal end thereof; rotating said hook to twist a first portion of the neck into a loop; tilting said hook to catch a second portion of the neck with said gripping means; moving said hook and said stretching means apart, so as to draw said looped first portion of the neck off the hook and past the gripped second portion of the neck, to form a knot; and releasing said gripping means to release said balloon. 